Bao Wuping, Lin Yanmei, Zhao Lei, Zhang Yingying, Lin Jingwang, Yin Junfeng, Wu Yiting, Wu Jifei, Zhou Yan, Zhang Min
Department of Respiratory and Critical Care Medicine, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
School of Mathematical sciences, Tongji University, Shanghai, China.
J Allergy Clin Immunol Pract. 2025 Jan;13(1):107-118.e8. doi: 10.1016/j.jaip.2024.10.010. Epub 2024 Oct 17.
Small-airway function assessment is crucial for asthma diagnosis and management. Abnormalities in terminal airflow deserve attention.
This study investigated whether (FEV-FEV)/FVC correlates with airway hyperresponsiveness (AHR) and inflammation in patients with preserved spirometry.
This cross-sectional study enrolled patients with FEV of 80% predicted or greater, FEV/FVC of 0.7 or greater, and recurring asthma-like symptoms. Data included demographics, FeNO, impulse oscillometry, and spirometry. Univariate and combined models predicting AHR were analyzed in 553 patients and validated in 561. We also assessed correlations between sputum inflammation and spirometrics.
Airway-hyperresponsive patients exhibited higher (FEV-FEV)/FVC ratios compared with those who were negative for AHR. This ratio showed the strongest association with the methacholine dose causing a 20% FEV decrease and the response dose ratio (r = -0.26 and 0.39, respectively; P < .001 for both). The area under the receiver operating characteristic curve for AHR diagnosis using (FEV-FEV)/FVC was 0.751, increasing to 0.821 when it was combined with FeNO, as confirmed in the validation cohort. Moreover, (FEV-FEV)/FVC was superior to maximal expiratory flow at 50% of FVC for identifying eosinophilic airway inflammation characterized by elevated FeNO levels. It correlated better with sputum eosinophil count than with the other spirometrics.
Elevated (FEV-FEV)/FVC levels were evident in AHR-positive patients with preserved FEV/FVC ratios. They serve as a sensitive marker of AHR and airway inflammation correlating with the response dose ratio, a provocative dose causing a 20% fall in FEV, and sputum eosinophils, suggesting their utility in monitoring patients at risk for uncontrolled asthma.
小气道功能评估对哮喘的诊断和管理至关重要。终末气流异常值得关注。
本研究调查了在肺量计检测结果正常的患者中，（第一秒用力呼气容积-用力呼气容积）/用力肺活量（FEV-FEV）/FVC是否与气道高反应性（AHR）及炎症相关。
这项横断面研究纳入了第一秒用力呼气容积（FEV）达到或超过预测值80%、FEV/FVC为0.7或更高且有反复哮喘样症状的患者。数据包括人口统计学信息、呼出一氧化氮（FeNO）、脉冲振荡法和肺量计检测结果。在553例患者中分析了预测AHR的单变量和联合模型，并在561例患者中进行了验证。我们还评估了痰液炎症与肺量计检测指标之间的相关性。
与AHR阴性患者相比，气道高反应性患者的（FEV-FEV）/FVC比值更高。该比值与导致第一秒用力呼气容积下降20%的乙酰甲胆碱剂量及反应剂量比值的相关性最强（分别为r = -0.26和0.39；两者P均<0.001）。使用（FEV-FEV）/FVC诊断AHR的受试者工作特征曲线下面积为0.751，在验证队列中与FeNO联合使用时增至0.821。此外，对于识别以FeNO水平升高为特征嗜酸性粒细胞性气道炎症，（FEV-FEV）/FVC优于50%用力肺活量时的最大呼气流量。它与痰液嗜酸性粒细胞计数的相关性优于其他肺量计检测指标。
在FEV/FVC比值正常的AHR阳性患者中，（FEV-FEV）/FVC水平升高明显。它们是AHR和气道炎症的敏感标志物，与反应剂量比值、导致第一秒用力呼气容积下降20%的激发剂量以及痰液嗜酸性粒细胞相关，提示它们在监测未控制哮喘风险患者中的效用。
